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Questions tagged [jpeg]

JPEG is a lossy-compression method for a digital image. The images can end up in many JPEG image containers (JPEG, JPG, JIF, JPE, JFI, JFIF) depending on the parameters surrounding the compression of the image data. JPEG is actually an acronym for Joint Photographic Experts Group, the group that created the compression standard for JPEG.

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Batch converting PNG to JPG in linux

Does anyone know a good way to batch-convert a bunch of PNGs into JPGs in linux? (I'm using Ubuntu). A png2jpg binary that I could just drop into a shell script would be ideal.
nedned
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Meaningful thumbnails for a Video using FFmpeg

FFmpeg can capture images from videos that can be used as thumbnails to represent the video. Most common ways of doing that are captured in the FFmpeg Wiki. But, I don't want to pick random frames at some intervals. I found some options using…
d33pika
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Opened a JPG picture with notepad, pasted all the "text" to a new notepad file, changed to .JPG and it no longer opens. Why?

This phenomenon has been leaving me questions to ask. Here is the detailed experiment, my OS is Windows 7 x64 SP1: I changed a picture (JPG) file to TXT by simply changing its extension (or one could just choose to open the JPG with notepad, same…
Nguyễn Tuấn Danh
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Removing Background color in Paint.net

I have a .jpg image of a text logo, it looks similar to the example image here: I am using paint.net. Now, I would like to change the image to .png, then I would like to remove all the white background, and make the image black text on a…
Greeso
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Convert a bunch of BMP files to JPEG on Linux

Someone sent me a bunch of BMP files and I need them in JPEG. I could convert them one by one using GIMP, but I'd rather do it all in one go. I have Ubuntu.
JoelFan
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JPEG vs PNG vs BMP vs GIF vs SVG

I would like to know which one of these formats requires less memory for the same quality of the picture, and what are the main differences between these formats.
Narek
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Search for a JPG on my computer by using a smaller JPG?

I have a low resolution image that I know I have the full resolution image stored somewhere on my computer. Is there anyway to search for a JPG on my computer by using a small resolution of an image as an input to search for?
AAA
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Why does Google Chrome save a JPG image to WEBP instead?

I'm trying to save what appears to be a JPG image from Chrome and always end up downloading a WEBP image instead. I'm on Chrome Version 80.0.3987.163 on macOS Catalina (10.15.4) and I'm trying to download a JPG image from a website. Even though the…
frabonomi
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How to convert a photo to a black and white image by ImageMagick?

How can I convert a JPEG photo to black and white (not grayscale) image like output of a FAX scanner, by ImageMagick?
ohho
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What is the largest size of a 640x480 JPEG?

I'm creating a data storage device that takes a certain number of pictures of the night sky over a couple of hours, and the pictures will be downloaded right after they are all taken. The memory card must be able to store all of the pictures at…
Blue Ice
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How to disable WebP images in Chrome?

Google Chrome sometimes takes a .jpg image and converts it to a .webp file. The problem is that when I save this image to file, I cannot open the file. I have tried manually changing the extension of the file to ".jpg", but the file is still…
rubik's sphere
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How can I modify the EXIF orientation tag of an image?

I want to change the EXIF orientation tag in my JPEG images but without actual rotating of them. I want to do this to use them as a test case for an application I made. How I can do that in Linux? Can I do it with exiftool? And if so, how?
Wazery
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How to find the JPG quality?

When I save a JPG file with GIMP, I can adjust the quality I save it at, from 0-100 (I use 89). It seems like I've used an app to see what this number was on saved file but if I did I can't for the life of me figure out what it was. Any suggestions…
Nathaniel
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Stop Windows 8 from converting wallpapers to low quality JPGs

This has been bugging me on Windows 7 as well, and much to my chagrin Microsoft didn't bother addressing that issue in Windows 8. Take this image for example: (Click to open original unaltered image.) It's made for retina Macbooks, so naturally…
Peter W.
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Is there any drawback to just renaming jpeg files to jpg?

A client sent me many jpeg files that I'd like to rename to jpg. Is this just a matter of renaming them, or should I open them with an image editing program and then saving them as jpg?
please delete me
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